The Southern Pacific No. X6454 Box Car is listed in the Production Table as Variations F through I, and was available from 1949 until 1952. They were usually equipped with Type 3b or Type 4 Staple-end trucks. The differences in the variations are:

Variation F: WHITE lettering on an LIGHT BROWN body and painted metal doors to match the body color. Has large lettering in early thinned lined railroad herald circles with a break in the outer circle. Chassis has steps at the four corners. Issued in 1949.

Variation G: Identical to Variation F except with WHITE small lettering and the chassis is without the steps at the four corners. 1950 production.

Variation H: WHITE lettering on a RED BROWN body and painted metal doors to match the body color. Has late thick lined railroad herald circles with no break in outer circle. Issued in 1951.

Variation I: WHITE lettering on a RED BROWN body and painted plastic doors that match the body color. Frequently found with Bar-end trucks. 1951-52 production.